Answer:
191433.4 hours
Explanation:
We are given that In the average US household, the television is on 6.75 hours/day! How many hours will have passed after 77.7 years (the average lifeexpectancy of an American)?
1 year - 365 days
Given that the television is on 6.75 hours/day.
If 1 year = 365 days
Convert 77.7 years to days by multiplying it by 365
77.7 × 365 = 28360.5 days
So the number of hours will be:
28360.5 × 6.75 = 191433.375 hours
Therefore, 191433.4 hours will pass.
Non of the options is correct.
Answer:
Thus the time taken is calculated as 387.69 years
Solution:
As per the question:
Half life of
= 28.5 yrs
Now,
To calculate the time, t in which the 99.99% of the release in the reactor:
By using the formula:

where
N = No. of nuclei left after time t
= No. of nuclei initially started with

(Since, 100% - 99.99% = 0.01%)
Thus

Taking log on both the sides:


t = 387.69 yrs
Answer with Explanation:
We are given that
Magnetic field,B=

Length of wire,l=15 m
Current,I=19 A
a.We have to find the magnitude of magnetic force and direction of magnetic force.
Magnetic force,F=
Using the formula


Direction=

15 degree above the horizontal in the northward direction.
Force = (mass) x (acceleration) (Newton's second law of motion)
Divide both sides of the equation by 'acceleration', and you have
Mass = (force) / (acceleration)
Mass = 17 newtons / 3.75 meters per second-sqrd = 4.533 kilograms (rounded)
Answer:
326149.2 KJ
Explanation:
The heat transfer toward and object that suffered an increase in temperature can be calculated using the expression:
Q = m*cv*ΔT
Where m is the mass of the object, cv is the specific heat capacity at constant volume, which basically means the amount of heat necessary for a 1kg of water to increase 1C degree in temperatur, and ΔT is the change in temperature.
A 65000 L swimming pool will have a mass of:
65000L *
= 65000 kg
The specific heat capacity at constant volume of water is equal to 4.1814 KJ/KgC.
We replace the data and get:
Q = m*cv*ΔT = 65000 kg * 4.1814 KJ/KgC * 1.2°C = 326149.2 KJ